1. Technical Field
The present invention relates an electrophoretic display device, an electronic apparatus including the electrophoretic display device, and a method of manufacturing the electrophoretic display device.
2. Related Art
As an electrophoretic display device, there is known a microcapsule-type electrophoretic display panel in which a microcapsule display layer is interposed between a pair of substrates (JP-A-2005-114822).
FIG. 15 is a schematic sectional view illustrating a microcapsule-type electrophoretic display panel. As shown in FIG. 15, a microcapsule type electrophoretic display panel 200 includes a microcapsule display layer 203 which is interposed between a transparent resin film 201 and a substrate 205, which serve as the pair of substrates.
In the microcapsule-type electrophoretic display panel 200, the microcapsule display layer 203 is formed by printing electronic ink containing microcapsules on a transparent electrode layer 202, which is formed on the transparent resin film 201 and serves as a common electrode, by screen printing.
Subsequently, after a first adhesive layer 204 is formed on the microcapsule display layer 203, the microcapsule display layer 203 of an area corresponding to the peripheral area of the panel and the first adhesive layer 204 are removed.
Subsequently, the substrate 205 is attached with the first adhesive layer 204 interposed between the substrate and the microcapsule display layer. On the substrate 205, pixel electrodes, thin film transistors corresponding to the pixel electrodes, signal electrodes, scanning electrodes are arranged (not shown).
A first moisture blocking resin layer 206 is formed in the peripheral area of the microcapsule display layer 203 by inserting a resin into a gap between the transparent resin film 201 and the substrate 205. Accordingly, the characteristics of the microcapsule display layer 203 may effectively be prevented from deteriorating due to invasion of moisture.
Examples of the material of the transparent resin film 201 serving as one substrate include polyethylene terephthalate, polymethylmethacrylate, polycarbonate. The substrate 205 serving as the other substrate is formed of a glass substrate or a resin film.
Examples of the first moisture blocking resin layer 206 include thermal or ultraviolet curable acrylic resin, metacrylate resin, and epoxy resin.
In the microcapsule-type electrophoretic display panel 200, when one pair of substrates is formed of glass, for example, the linear expansion coefficient of the pair of substrates is smaller than the linear expansion coefficient of the first moisture blocking resin layer 206. For example, when a thermal shock test or a thermal cycle test is carried out at a temperature from −20° C. to 85° C. as a reliability test, a local stress occurs between the first moisture blocking resin layer 206 and one pair of substrates depending on the different linear expansion coefficients. Processing strains such as micro cracks in a cutting process may occur in the outer edges of the glass substrates. For this reason, when a crack occurs due to the processing strain of the local stress, the glass substrates may be broken.
When the glass substrates are broken, electric damage may occur in the electrodes formed on the glass substrates. Then, problems may arise in that reliability may deteriorate since display defects occur and moisture invades.